[Roman Mostazir]

You should read the help file for `zscore06'. If you are supplying right information for a, s, w and h the generated values should be correct. From here in my part, I cannot confirm what your hc1 or hc27 variables contain as you have not supplied enough data information. However, `zanthro' as shown in post#14 also calculates z-scores based on WHO-2007 reference data. In that case the code shown in #14, needs to be replaced with WHO in place of UK. I am wondering why you would use an older version of reference data (2006) while an updated (2007) referencing is in place. The updated version is supposed to be more precise. However, call is yours.

[Mangji Zo]

What is the best way to graphically represent HAZ, WHZ scores in Stata? Can I use a Kdensity plot? I have seen it used for weights but not sure? Any advice is greatly appreciated!

[Mangji Zo]

Thanks, Roman! I did not know there is an updated version of WHO reference! But I will use that instead! Thanks! Really helpful!

[Mangji Zo]

Hi Roman, sorry for the multiple posts. I have tried egen zwhwho= zanthro(height, wh, WHO), xvar(child_age) gender(Sex_childnew) gencode(male=1, female=2) to generate WHZ scores but STATA is telling me that all the data is missing. I am not sure what I am doing wrong since I generated HAZ with no problem. Thanks!

* Example generated by -dataex-. To install: ssc install dataex
clear
input float(length height) double(weight Sex_childnew zhawho) byte child_age
   .  71.5  9.8 2                   . 31
66.8     . 18.3 1                   .  8
   .  96.1 12.8 2  -.2509602784699207 39
79.4     .  9.6 2                   . 20
   . 107.3 15.5 1   3.965068233654363 32
   .  99.7 13.6 2  -.7037006565044963 48
   .  85.2 10.9 1 -1.7858814857679666 29
   .  93.9 14.2 1 -1.2183544805521178 40
   . 105.6 16.8 1  -.2416348117221642 54
   .     .    . 2                   . 37
   . 106.9 17.1 1 -.31380133142305616 57
64.5     .  7.4 2                   .  7
   .  81.3 11.4 1  -2.141227523186235 25
   .    94 15.2 1 -1.7404155210822942 44
   .     .    . 2                   . 42
   .     .    . 2                   . 48
   .  97.6 15.5 1  -1.241957601178433 47
   .     .    . 2                   . 36
87.9     . 11.9 1                   . 23
67.2     .  7.2 2                   . 11
   .  86.1 12.7 2 -2.0288184053822897 34
86.9     . 12.9 1                   . 10
   .     .    . 1                   . 14
   .     .    . 1                   . 42
   .  97.3 16.6 1  1.1175622435815848 32
   .  82.6 10.3 2 -1.8944676946577002 28
   . 100.3 13.7 1    3.00291101320528 28
   .  82.9 10.4 1  -1.349195998616809 23
74.7     .    8 2                   . 14
   .  92.5 12.7 2 -.49240796460061287 35
   .    99 15.8 2  -.7347253748863545 47
72.1     .  7.2 2                   .  7
   .  92.2 12.4 2  -.7488652897948382 36
   .  90.4 11.6 1 -1.5332217555157286 36
   .  81.6   11 1  -.9238263428411112 20
  75     . 11.4 2                   .  .
  67     .    8 2                   .  9
   .     .    . 1                   . 48
   . 102.2   15 1  -.7738051888439137 52
   .     .    . 2                   . 30
   .  97.3   13 2 -2.0618317661231442 55
   .  73.6  9.4 2 -1.0363805136312814 14
   . 106.3 17.2 1   .4341195321577986 50
   .  84.5  9.9 2 -1.1188198625419832 27
   .   110 16.4 2   .5901738773589686 56
   .  83.8 11.5 2  -.5420247939571156 23
   .     .    . 2                   . 44
   .     .    . 1                   .  8
  68     .  8.2 2                   . 12
   . 101.1 15.9 2 -.10258150588117262 46
   .  96.1 13.2 2  -.7242878153992933 42
   .  84.5 12.2 2  -.8847569766593962 26
   .  92.5 12.6 2  -1.318478897741691 40
   . 104.6   17 2  .43384536027346104 48
90.9     .  8.2 1                   . 20
   .  86.5   13 2  .30872839907370647 23
   .  90.3 12.2 1  -.2635171437074367 29
   .     .    . 1                   .  6
  69     .  8.5 1                   .  8
   .  88.1 11.6 2  -.9342785473977289 31
   . 102.4 20.2 2  -.7146958653441926 53
   .     .    . 1                   . 28
   . 100.6   14 2  1.4571548208415361 36
76.2     .  8.7 1                   . 13
   .     .    . 1                   . 36
74.2     .  9.6 1                   . 12
   .     .    . 1                   . 40
   .  89.2 12.3 2 -1.0140366479505047 33
68.3     .  7.8 1                   .  6
   . 107.5 16.2 2   .9619551494336944 49
   .    72 10.9 2  -.7825295162584806 12
   .     .    . 2                   . 43
   .     .    . 1                   . 35
   .  97.8 17.2 1  2.5284760505172357 27
   .  81.2 11.8 2 -1.3612714586267303 23
   .  87.5 14.2 1  -.8843531691477253 28
   .  78.5  9.5 2  -.7603304289054266 18
   .  97.7 14.5 1 -.23975668568961175 40
   .    67  7.7 1 -2.7489935724070906 10
95.9     . 14.4 1                   . 36
   .  86.4 13.4 2 -1.0052304053419383 29
   .  98.3 14.7 2 -1.9473224518636743 56
   .     .    . 1                   . 16
   . 100.8 14.7 1  -.4721229893283415 47
   .     .    . 1                   . 42
   .  96.3 16.8 2  1.5920805676099052 30
   .  95.2 14.7 1 -2.4927287342088844 53
   .    91 12.7 2 -3.2490803032739497 53
   .  87.5   12 2 -1.9831850403102425 36
67.5     .  7.4 2                   . 17
   . 100.5 15.5 2 -1.2511161760105243 54
   .     .    . 2                   . 47
   .  73.3  9.8 1                   . 30
   .  87.8 13.7 1  -.3169360200322796 26
68.9     .    7 2                   .  8
83.4     .  9.8 2                   . 20
74.5     .  9.2 2                   . 11
81.5     .  9.9 1                   . 48
67.6     .  8.3 2                   . 16
   .  96.1 14.6 2  -.2509602784699207 39
end

------------------ copy up to and including the previous line ------------------

Listed 100 out of 2385 observations
Use the count() option to list more

[Roman Mostazir]

Not surprising as you are not supplying the right function. For weight for height, the help file says:

 WHO Child Growth Charts and WHO Reference 2007 Charts, version WHO

    chart        Description           Measurement      xvar() range
                                          unit
    -----------------------------------------------------------------------------
   
     wh       weight-for-height             kg          65-120 cm
    -----------------------------------------------------------------------------

So the `xvar' should be `height' measured in centimeter, while your code shows you spplied 'age' as 'xvar'. The correct code should be:

egen zwhwho= zanthro(weight, wh, WHO), xvar(height) gender(Sex_childnew) gencode(male=1, female=2)

su zwhwho


    Variable |        Obs        Mean    Std. Dev.       Min        Max
-------------+---------------------------------------------------------
      zwhwho |         58    .0696337     1.02973  -1.498012    2.47259

[Mangji Zo]

Thanks, Roman! I realized my mistake this morning! Thanks for your post and corrections!

My other question is what is the best way to graph this HAZ and WHZ scores in STATA? I use a histogram but are there better options to graphically represent the scores?

Thanks for any advice!

[Roman Mostazir]

Apologies, I do not know. I do not work with these sort of data or program. I was able to help you just because your coding mistake was easy to spot as you have identified by yourself. Hope someone else can help or relying on Google image search may be a good idea initially!

[Mangji Zo]

Okay, thanks Roman! I really appreciate your help! Learned a lot about converting z scores!

[tes had]

Zanthro seems an old version. Anyone who can help with zscore06 stata command?